Patent CA497166A successfully refreshed from Google Patents.
US5116767A
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Semiconductor laser passivation and overstressing
Assignee: Nytell Software LLC
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Filing: 1991-09-09
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Granted: 1992-05-26
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Expires: 2011-09-09
Abstract
Abstract A method for imnproving the reliability of InGaAsP lasers in which the lasers are subjected to sulfide passivation so as to passivate defects on their facets. The lasers are then tested to determine whether any laser has an internal defect. For examples, all lasers can be tested at an electrostatic discharge (ESD) level which would cause any laser having an internal defect to fail. Failed lasers are discarded. The passivation greatly increases the ESD failure level for facet defects, and the ESD screening removes those lasers having internal defects. Thereby, those lasers remaining in the lot have greatly increased reliability to ESD.
Inventors
- 👤 Louis F. DeChiaro
- 👤 Claude J. Sandroff
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 19:55
CPC Classifications
H; H01; H01S; H01S5/00; H01S5/02; H01S5/028; H01S5/0282; H01S5/0014; H01S5/0021; H10; H10H; H10H20/00; H10H20/01; H10H20/011; H10H20/013; H10P; H10P14/00; H10P14/60; Y; Y10; Y10S; Y10S148/00; Y10S148/095; Y10S438/00; Y10S438/958
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
88 words
A method of passivating and screening semiconductor lasers, comprising the steps of: determining an electrostatic discharge failure level associated with internal defects of a type of InGaAsP semiconductor lasers; sulfide passivating a plurality of said type of lasers having at least one exposed end facet, said plurality constituting a lot; electrostatic discharge stressing said plurality of lasers to a stressing corresponding to said failure level; testing each of said stressed lasers to determine whether it is a failed laser; and removing each said failed laser from said lot.
Claim 2
Independent Claim
88 words
A method of passivating and screening semiconductor lasers, comprising the steps of: determining an electrostatic discharge failure level associated with internal defects of a type of InGaAsP semiconductor lasers; sulfide passivating a plurality of said type of lasers having at least one exposed end facet, said plurality constituting a lot; electrostatic discharge stressing said plurality of lasers to a stressing corresponding to said failure level; testing each of said stressed lasers to determine whether it is a failed laser; and removing each said failed laser from said lot.
Claim 3
Dependent Claim
20 words
A method as recited in claim 1, wherein said electrostatic discharge stressing comprises applying a forward-bias pulse to said lasers.
Claim 4
Dependent Claim
37 words
A method as recited in claim 2, wherein said stressing level is above a stress failure level associated with said internal defects and is below a stress failure level of said type of lasers after sulfide passivation.
Claim 5
Dependent Claim
17 words
A method as recited in claim 2, wherein said forward-bias pulse has a voltage above 4 kV.
Claim 6
Dependent Claim
18 words
A method as recited in claim 4, wherein said voltage of said forward-bias pulse is below 6 kV.
Claim 7
Dependent Claim
20 words
A method as recited in claim 1, wherein said InGaAsP lasers emit at a wavelength between 1.3 and 1.55 μm.
Claim 8
Independent Claim
80 words
A method of screening lasers, comprising the steps of: sulfide passivating at least one exposed facet of a plurality of InGaAsP semiconductor lasers, said plurality constituting a lot; measuring a lasing optical output spectrum for each of said lasers in said lot; and comparing said measured spectrum to a reference spectrum for each of said lasers in said lot and removing any of said lasers from said lot if its measured spectrum does not adequately conform to said reference spectrum.
Claim 9
Independent Claim
80 words
A method of screening lasers, comprising the steps of: sulfide passivating at least one exposed facet of a plurality of InGaAsP semiconductor lasers, said plurality constituting a lot; measuring a lasing optical output spectrum for each of said lasers in said lot; and comparing said measured spectrum to a reference spectrum for each of said lasers in said lot and removing any of said lasers from said lot if its measured spectrum does not adequately conform to said reference spectrum.
Claim 10
Dependent Claim
19 words
A method as recited in claim 7, wherein said measuring step is performed prior to said sulfide passivating step.
Claim 11
Dependent Claim
18 words
A method as recited in claim 7, wherein said measuring step is performed after said sulfide passivating step.
References Cited (Backward Citations)
US4751200A
Cited
US4751201A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1995-05-26 | 1995-11-25 | 1996-05-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-05-26 | 1999-11-25 | 2000-05-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2003-05-26 | 2003-11-25 | 2004-05-26 | $7700.00 | Window Closed / Lapsed |